This invention relates generally to skylight apparatus and, more particularly, to a skylight apparatus which has a thermal insulation capacity which is significantly greater than is presently available in conventional skylight apparatus.
One of the disadvantages which conventional skylight apparatus presents is the relatively large extent of leakage of thermal energy which takes place through the marginal areas thereof. Thus, for example, in skylights of the dome type, i.e., where the skylight window element has a dome-shaped portion, the spacing between the window elements is insignificant at their marginal or peripheral areas. By virtue of this fact, the thermal insulating capacity of the skylight apparatus at these marginal areas is virtually non-existent. The fact that a high thermal insulative capacity usually exists at the central portions of the window elements obtains a secondary importance when the insignificant thermal insulative capacity at the marginal regions is considered.
Although there is known in the prior art skylight apparatus wherein the marginal areas of vertically adjacent window elements are mutually spaced from each other, such prior art apparatus does not solve the thermal insulation problem discussed above. More particularly, skylight apparatus is disclosed in German publicizing print No. 1,260,753 wherein window element supporting members are provided having opposed portions the distance between which decrease in the downward direction and wherein two window elements of different size are supported thereby. In this structure, the supporting members are defined by the marginal areas of the skylight aperture and the vertically adjacent window elements have marginal areas which are mutually spaced from each other for the primary reason of preventing the formation of condensate. As mentioned above, however, such known apparatus does not solve the problem of heat loss through the marginal areas of the skylight apparatus.